/*
 * Licensed to Crate under one or more contributor license agreements.
 * See the NOTICE file distributed with this work for additional
 * information regarding copyright ownership.  Crate licenses this file
 * to you under the Apache License, Version 2.0 (the "License"); you may
 * not use this file except in compliance with the License.  You may
 * obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
 * implied.  See the License for the specific language governing
 * permissions and limitations under the License.
 *
 * However, if you have executed another commercial license agreement
 * with Crate these terms will supersede the license and you may use the
 * software solely pursuant to the terms of the relevant commercial
 * agreement.
 */

package io.crate.data;

import java.util.Collections;
import java.util.Iterator;

public interface Bucket extends Iterable<Row> {

    Bucket EMPTY = new Bucket() {
        @Override
        public Iterator<Row> iterator() {
            return Collections.emptyIterator();
        }

        @Override
        public int size() {
            return 0;
        }

        @Override
        public String toString() {
            return "Empty Bucket";
        }
    };

    /**
     * Returns the number of rows in this bucket.
     *
     * @return the number of rows
     */
    int size();
}
